Why isn’t Cam Smith getting more time in the infield with Peña out?

I’m scratching my head wondering why Cam Smith isn’t getting some reps at short or even third. He’s a natural infielder, right? Seems like a prime opportunity to get him some big-league chops on the left side of the dirt. Are there concerns with his defense at the MLB level? Is it just a roster jam thing? Development plan? I’m not seeing the downside to testing his glove a bit more with Peña down.